Primary network heat supply flow balance adjustment and primary pipe network resistance reduction system operation method

Abstract

The invention relates to the technical field of central heating, and discloses a primary network heat supply flow balance adjustment and primary pipe network resistance reduction system operation method, which comprises the following steps: accurately calculating the final target flow of each branch pipeline through a flow demand evaluation model integrating static physical parameters and dynamic operation parameters; and then, a two-stage strategy of coarse adjustment and fine adjustment is adopted, a specific cooperative operation principle is followed, and standardized operation is conducted on the adjusting valve, so that the actual flow accurately approaches the target flow. In order to solve the intractable problem that the flow still does not reach the standard after the adjusting valve is fully opened due to physical blockage, the method further comprises closed-loop monitoring and intelligent diagnosis, faults such as insufficient flow or low heat exchange efficiency can be automatically recognized, and a flow distribution model is fed back and optimized. Accurate distribution of heat supply flow is achieved, the problem of intractable blockage of a pipe network is effectively solved, and the operation efficiency and heat supply quality of a heat supply system are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of centralized heating technology, and in particular to a method for adjusting the primary network heating flow balance and operating a primary network resistance reduction system. Background Technology

[0002] In centralized heating systems, the hydraulic balance of the primary heating network is a core prerequisite for ensuring on-demand heating at each heating station, guaranteeing heating quality for end users, and achieving energy-saving and consumption-reducing operation of the entire system. In existing technologies, the flow balance regulation of the network largely relies on the on-site experience of operators, achieved through manual adjustment of valves in each branch pipeline. This method often results in unscientific setting of target flow rates, relying only on static data such as heating area, lacking comprehensive consideration of dynamic factors such as real-time weather changes and differences in building insulation performance, leading to insufficient accuracy in flow distribution.

[0003] At the same time, the adjustment process itself is also blind. Adjusting a branch can trigger a chain reaction of changes in the hydraulic conditions of the entire pipeline network, interfering with the flow of other branches. This makes the adjustment work need to be repeated, time-consuming and laborious, and it is difficult to quickly reach a globally optimal equilibrium state.

[0004] Even more challenging is the situation when pipelines become physically blocked due to impurities, rust, and scale buildup from long-term operation. Conventional adjustment methods, such as opening valves to their maximum stroke, are completely ineffective in resolving the problem of severely insufficient flow. In such cases, existing solutions typically require shutting down the pipeline section, employing large-scale flushing or even excavation and replacement. This not only disrupts normal heating services for an extended period, affecting a wide area, but is also costly and time-consuming. Therefore, existing technologies are significantly inadequate in achieving precise flow allocation and addressing persistent pipeline blockages, lacking a systematic solution that combines accurate calculation, intelligent regulation, and efficient fault handling. Summary of the Invention

[0005] The purpose of this invention is to provide a method for regulating the primary network heating flow balance and reducing the resistance of the primary network, which solves the problems of imprecise flow distribution, low regulation efficiency, and lack of efficient and minimally invasive treatment methods for stubborn network blockages in existing heating technologies.

[0006] To achieve the above objectives, the present invention provides the following technical solution: The operation methods for primary network heating flow balance regulation and primary network resistance reduction system include: When the regulating valve of a branch pipe in a heat pipe network is fully open, and the actual flow rate is still lower than the preset final target flow rate, a network resistance reduction operation is performed on that branch pipe. The network resistance reduction operation includes: A new water pump is connected in parallel across both ends of the main valve of the primary return water pipeline in the heating station at the end of the branch pipeline; the primary return water main valve is closed to force the circulation path through the new water pump; the new water pump is started to provide pressurized circulation power for the blocked pipe section; Intermittently opening and closing the drain valve of a sludge separator located on a primary water supply pipeline to flush and discharge sediment from the pipeline using pressure pulse effects. Preferably, prior to performing the pipeline resistance reduction operation, the method further includes: The flow allocation strategy is formulated based on the static physical parameters and dynamic operating parameters of the heating network, and the final target flow of each branch pipeline is calculated through the flow demand assessment model. The flow balance regulation is implemented by initially adjusting the regulating valves of each branch pipeline according to the final target flow rate.

[0007] Preferably, after the pipeline resistance reduction operation is completed and the pipeline network is restored to normal operation, the method further includes: Closed-loop monitoring and feedback adjustment continuously monitors the operating parameters of each branch pipeline and adjusts the regulating valves based on the monitoring results.

[0008] Preferably, in the formulation of the traffic allocation strategy, the final target traffic is calculated in the following way: Calculate the real-time target heat load for each branch pipeline area; The theoretical flow rate of each branch pipeline is calculated based on the real-time target heat load. The theoretical flow rates of all branch pipelines are summed, and combined with the upper limit of the total circulating water volume set by the primary network, the theoretical flow rates of each branch pipeline are normalized by the global balance distribution coefficient and the user priority coefficient.

[0009] Preferably, the real-time target heat load is calculated as follows: The theoretical basic heat load GH is calculated by multiplying the heating area, the design heat index per unit area, and the comprehensive building characteristic correction factor. The real-time target heat load is calculated by multiplying the theoretical basis heat load GH, the meteorological correction factor, and the operational feedback correction factor.

[0010] Preferably, a diagnostic step is included before performing the pipeline resistance reduction operation: After checking and confirming that the dirt separator and heat exchanger equipment at the end of the branch pipeline heating station are not faulty or have excessive resistance, and after confirming that the pipeline design diameter meets the flow requirements, the cause of the fault is determined to be internal blockage of the pipeline.

[0011] Preferably, the static physical parameters on which the flow demand assessment model is based include at least: heating area, building use classification, building energy efficiency standards, pipeline terminal index, and user priority coefficient.

[0012] Preferably, the dynamic operating parameters on which the flow demand assessment model is based include at least: real-time outdoor temperature, real-time wind speed, and historical heat consumption data.

[0013] Preferably, the flow balance adjustment is implemented as follows: In the coarse adjustment stage, based on the final target flow rate, it is determined whether the deviation between the actual flow rate of each branch pipeline and the final target flow rate is greater than a preset coarse adjustment error threshold; if so, the opening of the regulating valve is adjusted to a larger range so that the actual flow rate quickly enters a relatively tolerant range near the final target flow rate. In the fine-tuning stage, based on the coarse-tuning, when the deviation is less than or equal to the coarse-tuning error threshold, the regulating valve is fine-tuned in a small-amplitude, iterative closed-loop manner by continuously comparing the current deviation between the actual flow rate and the final target flow rate, with the goal of a smaller allowable range of fine-tuning error, until the deviation is stably maintained within the allowable range of fine-tuning error.

[0014] Preferably, the operation of intermittently opening and closing the sewage outlet valve specifically involves rapidly opening and closing the sewage outlet valve at a cycle frequency of 0.5-4 times per minute; wherein the single opening stroke time or single closing stroke time of each valve is less than 2 seconds.

[0015] In summary, the present invention has at least one of the following beneficial technical effects: 1. This invention, by adding additional water pumps in parallel at both ends of the main valve of the primary return water pipeline and coordinating with the intermittent opening and closing of the drain outlet of the sludge separator on the primary supply water pipeline, can generate strong pressure pulses within the pipeline, thereby effectively stripping and removing stubborn deposits adhering to the pipe wall. This method solves the problem of physical blockage that conventional adjustment methods cannot address, can quickly restore the flow rate of the faulty pipeline, and ensure the heating effect in the local area.

[0016] 2. This invention achieves scientific and quantitative allocation of flow in each branch pipeline by constructing a flow demand assessment model. This model comprehensively considers static physical parameters such as building characteristics and pipeline topology, as well as dynamic operational parameters such as outdoor weather and operational feedback, to calculate the final target flow for each branch pipeline. This method replaces the traditional, coarse scheduling method that relies on manual experience, making heat allocation more precise and reasonable, and improving the quality and efficiency of the overall network's heating balance.

[0017] 3. This invention integrates flow distribution, standardized adjustment operations, goal-oriented fault handling, and dynamic closed-loop monitoring into a complete system operation method. This method not only covers flow balance adjustment under normal operation but also incorporates a specific and feasible process for handling persistent blockages, forming a closed-loop management system covering the entire process from strategy formulation and routine adjustment to fault diagnosis, special handling, and continuous optimization. This significantly enhances the adaptability and operational stability of the entire heating system in the face of various complex operating conditions. Attached Figure Description

[0018] Figure 1 This is a flowchart of the operating method of the present invention; Figure 2 This is a schematic diagram of the pressurized bridging sewage connection of the present invention. Detailed Implementation

[0019] The following is in conjunction with the appendix Figure 1 - Appendix Figure 2 The present invention will be further described in detail below.

[0020] This invention provides a method for regulating the primary network heating flow balance and operating a primary network resistance reduction system, which may include the following steps: S100: Traffic allocation strategy formulation; S200: Flow balance adjustment implementation; S300: Reduces resistance in stubborn pipeline networks; S400: Closed-loop monitoring and feedback adjustment.

[0021] The following will describe in detail the specific implementation of step S100, namely, the formulation of the flow allocation strategy. The function of this step is to calculate and determine the final target flow for each branch pipeline in the heating network. This calculation process is based on a flow demand assessment model, the data input of which comes from a basic data system consisting of static physical parameters and dynamic operating parameters.

[0022] Methods for collecting and quantifying static physical parameters. Static physical parameters are parameters that describe the physical properties of a heating system and remain constant or change slowly within a single heating season. Specifically, they include: Heating area (A): refers to the total heating building area served by each branch pipeline, which can be obtained by consulting design drawings or property files.

[0023] Building Use Classification: This refers to classifying buildings into different types such as residential buildings, public buildings, and industrial plants. This classification information is used to subsequently determine and correct thermal indicators.

[0024] Building energy efficiency standards refer to the energy efficiency design standards followed during the construction of buildings, such as energy saving of 50%, 65% or higher. This information is used to quantify the thermal insulation performance of building envelopes.

[0025] Pipeline end index: This is a dimensionless value used to quantify the physical location of a branch pipeline in the entire pipeline network topology. This value can be pre-calculated based on topological information such as the length of the pipeline from the heat source and the number of branches along the way, and is used to reflect the transmission distance and the degree of heat loss along the way.

[0026] User priority coefficient (P) prio ): This is a dimensionless value set according to heating service agreements or guarantee requirements (such as hospitals, schools, etc.) to adjust the flow allocation weight when the total flow is limited. This value is greater than or equal to 1.

[0027] Methods for acquiring and quantifying dynamic operating parameters. Dynamic operating parameters are parameters that describe the real-time changing environment and state of a system. Specifically, they include: Real-time outdoor temperature: acquired through temperature sensors deployed at one or more meteorological monitoring points within the heating area, and regional average calculations are possible.

[0028] Real-time wind speed: Acquired by wind speed sensors deployed in the heating area, this parameter is used to correct for additional heat loss caused by air convection.

[0029] Historical heat consumption data: refers to the heat consumption and actual flow data of each branch pipeline under different operating conditions extracted from the operation records of previous heating seasons, which is used for feedback correction of the model.

[0030] The calculation principle and process of the traffic demand assessment model. After obtaining the above parameters, the model derives the final target traffic (G) through the following three calculation processes. tgt ).

[0031] Theoretical basis heat load (Q) base The calculation details and physical meaning of each parameter are explained. This step calculates the theoretical heat energy demand of each branch pipeline area under standard design conditions. The calculation formula is as follows: Q base =A·q unit ·C bldg ; In this formula: A represents the total heating area served by the branch pipeline, in m². 2 .

[0032] q unit The design thermal index per unit area, which is applicable to this region, is a benchmark value based on local climate zones and standard building codes, and is expressed in W / m².2 .

[0033] C bldg It is a dimensionless coefficient and serves as a correction factor for comprehensive building characteristics.

[0034] This coefficient is calculated based on building use classification and building energy efficiency standards in static physical parameters. Its physical meaning lies in quantifying the standard q... unit The values ​​are adjusted to accurately reflect the differences in heat demand of a particular building complex due to its use (e.g., a kindergarten that requires higher room temperatures) or insulation performance (e.g., a building with higher energy efficiency standards that consumes less heat).

[0035] Real-time target heat load (Q) rt The calculation details and working mechanism of each correction factor are explained. This step dynamically corrects the base heat load based on the real-time changing operating environment. The calculation formula is as follows: Q rt =Q base ·C wthr ·C fdbk ; In this formula: Q base This is the theoretical basis heat load calculated in the previous step.

[0036] C wthr C is a meteorological correction factor, a dimensionless coefficient. Its mechanism of action lies in the fact that it is a function related to real-time outdoor temperature and real-time wind speed. When the outdoor temperature decreases or the wind speed increases, C... wthr The value will be greater than 1, thus increasing the real-time target heat load; conversely, it will be less than 1. Its function is to quantify the actual impact of current meteorological conditions on the theoretically based heat load.

[0037] C fdbk The feedback correction coefficient is a dimensionless coefficient. Its mechanism involves comparing historical heat load data with the model's calculated values ​​under corresponding historical operating conditions, and iteratively adjusting the coefficient based on the deviation. Its function is to fine-tune the heat load calculation based on historical operating performance, enabling the model to have self-calibration and error correction capabilities.

[0038] Ultimate target traffic (G) tgt The calculation and global balance allocation method of heat load demand in each region. This step converts the heat load demand of each region into... This is transformed into specific, executable traffic commands, ensuring that the total network traffic meets the constraints. The calculation formula is as follows: In this formula: G tgtThe final calculated target flow rate for the branch pipelines, issued to the regulating and executing stage, is expressed in kg / s.

[0039] Q rt This is the real-time target heat load calculated in the previous step.

[0040] c p ρ is the specific heat capacity of water, a physical constant with units of J / (kg·℃).

[0041] ΔT is the supply and return water temperature difference designed for the primary network system. It is a system design parameter, and its unit is °C.

[0042] P prio The user priority coefficient is derived from static physical parameters and is a dimensionless number.

[0043] R alloc The coefficient for global balancing is a dimensionless coefficient. The implementation of global balancing is as follows: The theoretical flow rate of all branch pipelines in the entire network without any adjustments (i.e. The summation is performed to obtain a theoretical total flow rate; then, the upper limit of the total circulating water volume set for the primary network is divided by this theoretical total flow rate to obtain the coefficient R. alloc .

[0044] R alloc The implementation method ensures that, under conditions of limited total circulating water volume, all priority-adjusted final target flow rates (G) are achieved. tgt The sum of these values ​​is strictly equal to or does not exceed the upper limit, thus achieving on-demand scientific allocation under the condition of satisfying constraints.

[0045] The following will describe in detail the specific implementation method of step S200, namely, the flow balance adjustment. The input for this step... The final target flow rate (G) of each branch pipeline calculated in step S100. tgt Its execution target is the electrically controlled regulating valve installed at the inlet of each branch pipeline, and its final output is the actual flow rate (G) of each branch pipeline. actual Within a preset precision error range, its final target flow rate (G) tgt To ensure stable hydraulic conditions, this embodiment adopts a two-stage adjustment strategy of "coarse adjustment followed by fine adjustment," and supplemented by the principle of coordinated operation to ensure the speed and stability of the adjustment process. This is achieved by considering the nonlinear relationship between the opening of the regulating valve and the pipeline flow rate, as well as the hydraulic coupling effect between the branches in the pipeline network.

[0046] The coarse adjustment phase (S210) is executed first. The triggering condition for this phase is determined by the following formula: |Gtgt -G actual |>ε1; Here, ε1 is a preset first threshold, which defines the starting boundary for coarse adjustment. The value of ε1 can be set according to the requirements for adjustment speed, and its calculation formula is: ε1=α1·G tgt ; Wherein, α1 is the coarse adjustment threshold coefficient, which is a dimensionless number and its value ranges from 0.10 to 0.15; Once coarse adjustment is triggered, the control system will calculate a one-time, relatively large step valve opening adjustment (ΔOrough) based on the current flow deviation. The calculation formula is a proportional control model: ΔO rough =K P ·(G tgt -G actual ); K P This is the proportional gain coefficient of the valve, expressed as a percentage opening per (kg / s).

[0047] This coefficient is obtained through offline calibration or online self-tuning of a specific valve and its corresponding pipe section. The new valve opening (O) after adjustment. next )for: O next =O current +ΔO rough ; Among them, O current This represents the valve's current opening degree before adjustment. The goal of the coarse adjustment phase is to quickly converge the flow deviation to within the first threshold (ε1).

[0048] Once the actual flow rate falls within the coarse adjustment range, the system automatically switches to the fine adjustment stage (S220). The triggering condition for this stage is determined by the following formula: ε2<|G tgt-G actual|≤ε1; Here, ε2 is a preset second threshold, which defines the target accuracy that the final adjustment needs to achieve. The formula for calculating ε2 is: ε2 = α2·G tgt ; Wherein, α2 is the fine-tuning threshold coefficient, which is a dimensionless number and its value ranges from 0.01 to 0.03.

[0049] The fine-tuning phase is a small-step, iterative approximation process. During this phase, the valve opening is adjusted by a fixed, minute increment (ΔO). fine For example, 0.5% of the total valve stroke.

[0050] In the nth iteration, the formula for adjusting the valve opening is: O n+1 =O n +ΔO fine ·sgn(G tgt -G actual,n ); Among them, O n+1 and O n These are the valve openings for the (n+1)th and nth iterations, respectively; G actual,n The actual flow rate is measured after the nth iteration adjustment action is completed and after a complete hydraulic stabilization cycle. sgn(·) is a sign function, which determines whether to open or close the valve based on the direction (positive or negative) of the flow deviation.

[0051] The stability criterion for the fine-tuning phase, i.e., the termination condition for this phase, comprises both accuracy and stability. This criterion is defined by the following set of formulas: Among them, G actual (t i ) is at the measurement time t i The actual flow rate value collected; N is the number of measurement cycles required to continuously meet the accuracy conditions, for example, N=3; Δt sample The data sampling time interval used to determine stability, for example, Δt. sample = 5 minutes. When the flow rate measured in each of the N consecutive sampling periods meets the accuracy requirements, the flow balance adjustment operation of this branch pipeline is considered complete.

[0052] To ensure the stability of the hydraulic conditions of the entire pipeline network during the adjustment process, this embodiment also follows specific cooperative operation principles and hydraulic condition stabilization measures during adjustment.

[0053] The principle of coordinated operation is specifically a sequential adjustment principle of "from far to near." That is, adjustment operations are not carried out in parallel on all branch pipes, but sequentially according to the order of hydraulic transport in the pipe network topology. During operation, the branch pipe furthest from the heat source or with the greatest hydraulic resistance is selected first, and a complete coarse and fine adjustment process is performed on it until its flow rate meets the aforementioned stability criteria. Subsequently, the next furthest or next least unfavorable branch pipe is selected for adjustment, and so on. The technical mechanism of this principle lies in establishing a stable downstream pressure boundary for the adjustment of upstream and adjacent pipes by prioritizing the stabilization of the hydraulic conditions downstream and at the end of the pipe network, thereby greatly reducing the hydraulic coupling interference between the adjustment operations of each branch.

[0054] Hydraulic condition stabilization measures refer to the requirement that after each valve opening adjustment, whether coarse or fine, the control system must wait for a preset "stabilization waiting period" (Δt). wait The technical basis of this measure is overcoming the physical inertia of the pipeline system, namely, the time required for fluid to reach a new steady-state flow velocity and pressure distribution within the pipeline. The duration of the waiting period (Δt) wait The settings can be configured based on the physical characteristics of the pipeline, and the settings should meet the following conditions: Δt wait >L / v; Where L is the pipe length from the regulating valve to the flow measurement point, and v is the design flow velocity of that pipe section. By forcing a sufficient waiting time, it is ensured that the data collected by the flow sensor after each adjustment truly reflects the steady-state value of the new operating condition, rather than the fluctuating instantaneous value. This is the technical basis for the correct convergence of the entire closed-loop control algorithm and the avoidance of system overshoot or oscillation.

[0055] The following will describe in detail the specific implementation method of step S300, namely, resistance reduction in persistent pipeline networks. This step is a special fault handling procedure initiated when conventional flow regulation methods fail. Its purpose is to address persistent flow loss problems caused by internal physical blockages in the pipeline that cannot be resolved by adjusting valves.

[0056] First, the triggering conditions and diagnostic process for resistance reduction operation are explained. The triggering condition for this operation is objective and unique. Its objective definition is: during the execution of step S200, the actual opening degree (O) of the regulating valve in a certain branch pipeline. actual It has reached its maximum travel (i.e., O). actual =100%), but the actual flow rate of this branch pipeline (G) actual Even after a complete hydraulic stabilization cycle, the flow rate is still significantly lower than the set final target flow rate (G). tgt ).

[0057] This state can be precisely described by the following formula: G actual <G tgt -ε2(whenO a ctual = 100%); Here, ε2 is the second threshold defined during the fine-tuning phase. When this condition is met, the system can determine that the branch pipeline has abnormal operating resistance and trigger subsequent diagnostic procedures.

[0058] The purpose of the diagnostic process is to differentiate the source of the fault to determine whether the unusual resistance originates from internal equipment within the heating station or from the external primary heating network pipelines. This process includes the following specific steps for troubleshooting internal equipment faults: Step 1: Inspect the sludge separator located on the primary water supply line of this branch line. Close the valves at both ends of the separator, and open the separator to check if the filter screen is severely clogged with impurities. If the filter screen is clogged, clean it, restore the system, and re-monitor the flow rate; if the filter screen is clean, proceed to the next step.

[0059] Step 2: Check the regulating valve itself. Assuming the control signal is correct, manually operate the valve locally or observe the valve stem position to confirm that the valve core inside the valve is indeed in the fully open position, ruling out the possibility of valve actuator malfunction or valve core jamming.

[0060] Step 3: If conditions permit, determine whether there is blockage or severe scaling inside the heat exchanger by measuring the pressure difference between the inlet and outlet of the plate heat exchanger in the primary water supply and return pipelines.

[0061] Once all the equipment within the station has been inspected and confirmed to be fault-free, it can be definitively determined that the unusual resistance in this branch pipeline originates from an internal physical blockage in the primary heating network pipeline outside the heating station. At this point, the "pressurization-boosting and bridging" resistance-reducing method is officially initiated.

[0062] The new water pump should be a portable centrifugal pump or pipeline pump with a head significantly higher than the supply and return water pressure difference of the branch pipeline during normal operation; for example, its head should be 1.5 to 3 times the normal pressure difference. Its rated flow rate should be sufficient to create an effective flushing velocity within the pipe section. The connecting pipes should be high-pressure resistant flexible pipes with a pressure rating higher than the maximum outlet pressure of the new water pump, and equipped with standardized quick couplings for easy on-site installation.

[0063] The specific location and installation method for the on-site connection are as follows: Within the target heating station, select the main control valve on the primary network return water pipeline. Connect the inlet end of the new water pump to the inlet side pipeline of this main control valve via a flexible pipe, and connect the outlet end of the new water pump to the outlet side pipeline of this main control valve via another flexible pipe. In this way, the new water pump and the primary network return water main valve connected to it form a parallel loop.

[0064] The operational steps of this method have been precisely broken down and described to ensure the safety and effectiveness of the operation: S310: After completing the above equipment connections, completely close the main control valve for the primary network return water that has been bridged. The purpose of this operation is to force the circulating water flow of the primary network to leave its main pipeline path and instead flow entirely through the bypass where the new water pump is located.

[0065] S320: Start the additional water pump. At this time, the water pump provides a powerful booster circulation force to the blocked pipe section, with a pressure differential much higher than that of normal operation.

[0066] S330: With the new water pump continuously running, the operator goes to the sludge separator located on the primary water supply line and performs intermittent, rapid opening and closing operations on its drain valve. For example, quickly open the valve for 5 seconds, then quickly close it for 10 seconds, and repeat this cycle.

[0067] The core principle of this method lies in the formation and action mechanism of the pressure pulse. During normal operation, the pressure within the pipe network is relatively constant. After starting the new water pump and closing the main return valve (S310, S320), a static pressure much higher than normal is established at the front end of the blocked pipe section. When the drain valve of the sludge separator is quickly opened (S330), the pressure at the drain outlet instantly drops to atmospheric pressure, causing water in the pipe to flow at high speed towards that point. When the drain valve is quickly closed again, the kinetic energy of the high-speed water movement is instantly converted into pressure energy, forming a shock wave with an extremely high pressure peak within the pipe—the pressure pulse. This intermittent opening and closing operation generates high-frequency, intense pressure oscillations in the area near the blockage. This pressure pulse exerts a powerful mechanical impact and shearing action on deposits (such as scale, silt, and rust) adhering to the inner wall of the pipe, causing them to break, loosen, and detach from the pipe wall. The detached impurities are then discharged from the drain outlet with the high-pressure water flow the next time the drain valve is opened.

[0068] The criteria for determining the completion of the operation are intuitive and objective: during step S330, continuously observe the water sample discharged from the drain outlet. Initially, the water sample will be extremely turbid and contain visible solid particles. As the operation continues, the turbidity of the water sample will gradually decrease. When the discharged water sample remains clear or nearly as clear as the primary water in several consecutive cycles, it can be determined that the main blockage in the pipeline has been cleared, and the resistance reduction operation is complete.

[0069] The system recovery process is the reverse of the resistance reduction operation, aiming to restore the pipeline network to its normal operating state. Step 1: Stop the operation of the new water pump and completely close the drain valve of the dirt separator.

[0070] Step 2: Slowly and completely open the primary network return water main control valve that was closed in step S310, so that the primary network water flow is restored to its main pipeline path.

[0071] Step 3: After confirming that the pipeline network is operating stably, remove the newly added water pump and its connecting pipes.

[0072] Step 4: Return system control and re-execute step S200 or step S400 to monitor and adjust the flow rate of the branch pipeline again.

[0073] The following will elaborate on the specific implementation of step S400, namely closed-loop monitoring and feedback adjustment. This step is the top-level monitoring and decision-making link of the entire operation method. Its function is to achieve closed-loop management and continuous optimization of the heating system's operating quality through continuous monitoring of the system's operating status, intelligent diagnosis based on preset logic, and feedback adjustment of control parameters.

[0074] First, the data acquisition and processing of the monitoring system will be explained.

[0075] This step uses a fixed acquisition period (Δt) sample For example, every 5 minutes, a set of key operating parameters is automatically collected by sensors deployed at each heating station. These parameters include: the actual flow rate of the primary network (G). actual The primary water supply temperature (T) is measured by a flow meter. 1,sup ) and primary network return water temperature (T 1,ret The secondary network water supply temperature (T) is measured by a temperature sensor. 2,sup ) and secondary network return water temperature (T 2,ret ), measured by a temperature sensor; and adjusting the current actual opening degree of the valve (O) actual The data is obtained through a valve position feedback device. The collected raw data undergoes preliminary processing to calculate a set of derived diagnostic parameters, primarily including the actual supply and return water temperature difference in the primary network (ΔT). 1,actual ) and actual heat exchange (Q) actual The calculation formulas are as follows: ΔT 1,actual =T 1,sup -T 1,ret Q actual =c p ·G actual ·ΔT 1,actual ; Among them, c p This is the specific heat capacity of water.

[0076] When the monitoring system detects that the heating quality of a certain branch pipeline is not up to standard (for example, its secondary network return water temperature T), 2,ret When the value remains below the set target value, the intelligent diagnostic logic will be automatically activated. This logic uses a series of conditional judgments to locate the root cause of the fault and generate targeted processing instructions.

[0077] The logic for diagnosing insufficient flow faults is as follows. After confirming that the heating quality is substandard, the system first checks the actual flow rate (G) of the branch pipe. actual ) and the final target flow rate (G) calculated in step S100 tgt Compare the results. If the following conditions are met: G actual <G tgt-ε2; Where ε2 is the second threshold for the fine-tuning stage defined in step S200. The system then determines the fault type as "insufficient primary network flow". At this time, the system will generate an instruction requiring the flow balance adjustment process of step S200 to be re-executed for this branch pipeline. If, during the re-execution of step S200, the opening degree of the regulating valve in this pipeline (O...) actual If the flow rate reaches 100%, but the condition of insufficient flow is still met, the system will further upgrade the fault diagnosis, determine it as "insistent excessive pipeline resistance", and generate an instruction to start step S300 to reduce the flow rate.

[0078] |G actual -G tgt |≤ε2; The logic for judging heat exchange efficiency faults is as follows.

[0079] If the heating quality is confirmed to be substandard, the flow rate comparison results must meet the following conditions: This condition indicates that the actual traffic of the primary network is sufficient and meets the standards.

[0080] At this point, the system will shift its diagnostic focus to the heat exchange stage. The system will calculate the current actual supply and return water temperature difference (ΔT) in the primary network. 1,actual ), and compare it with a theoretical minimum temperature difference threshold (ΔT) based on the current operating conditions. 1,threshold Compare the results. If the following conditions are met: ΔT 1,actual <ΔT 1,threshold ; The system then determines the fault type as "low heat exchange efficiency at the heating station." Physically, this means that sufficient hot water flows through the heating station, but the heat it carries is not effectively transferred to the secondary network. Based on this, the system will generate instructions requiring maintenance personnel to inspect the plate heat exchangers at the heating station (e.g., for scaling or blockage) and to troubleshoot the secondary network circulation system.

[0081] Finally, the implementation mechanism of closed-loop feedback adjustment is explained.

[0082] The closed-loop characteristic of this invention is not only reflected in fault diagnosis and handling, but also in the continuous optimization of the traffic allocation model. The implementation of this mechanism relies on feedback adjustment of the dynamic parameters of the traffic demand assessment model in step S100.

[0083] Specifically, the system will continuously monitor the operational data of each branch pipeline. If, on a certain branch pipeline, none of the aforementioned faults are triggered, but its secondary network temperature remains consistently too high or too low, the system will consider the operational feedback correction coefficient (C) set in step S100 to be applied. fdbkThere is a deviation. In this case, the system will automatically fine-tune the coefficient based on the direction and magnitude of the deviation. For example, for a branch that has been consistently underperforming, its new correction coefficient (C′) will be adjusted in the next calculation cycle. fdbk The following formula can be used for adjustment: C′ fdbk =C fdbk ·(1+δ); Where δ is a small positive adjustment factor.

[0084] In this way, even in the absence of a clear fault, the system can learn and correct its initial allocation strategy based on the actual operating results, thereby continuously improving the adjustment accuracy and balance of the entire heating system during operation, forming a complete closed-loop feedback adjustment with self-optimization capabilities.

Claims

1. A method for regulating the primary network heating flow balance and operating a primary network resistance reduction system, characterized in that, include: When the regulating valve of a branch pipe in a heat pipe network is fully open, and the actual flow rate is still lower than the preset final target flow rate, a network resistance reduction operation is performed on that branch pipe. The network resistance reduction operation includes: A new water pump is connected in parallel across both ends of the main valve of the primary return water pipeline in the heating station at the end of the branch pipeline; Close the primary return water main valve to force the circulation path through the newly added water pump; start the newly added water pump to provide pressurized circulation power for the blocked pipe section; Intermittently open and close the drain valve of the sludge separator located on the primary water supply line to flush and discharge sediment in the pipeline using the pressure pulse effect.

2. The method for adjusting the primary network heating flow balance and reducing the resistance of the primary pipeline system according to claim 1, characterized in that, Before performing the pipeline resistance reduction operation, the method further includes: The flow allocation strategy is formulated based on the static physical parameters and dynamic operating parameters of the heating network, and the final target flow of each branch pipeline is calculated through the flow demand assessment model. The flow balance regulation is implemented by initially adjusting the regulating valves of each branch pipeline according to the final target flow rate.

3. The method for adjusting the primary network heating flow balance and reducing the resistance of the primary pipeline system according to claim 2, characterized in that, After the pipeline resistance reduction operation is completed and the pipeline network is restored to normal operation, the method further includes: Closed-loop monitoring and feedback adjustment continuously monitors the operating parameters of each branch pipeline and adjusts the regulating valves based on the monitoring results.

4. The method for adjusting the primary network heating flow balance and reducing the resistance of the primary network as described in claim 2, characterized in that, In formulating the traffic allocation strategy, the final target traffic is calculated as follows: Calculate the real-time target heat load for each branch pipeline area; The theoretical flow rate of each branch pipeline is calculated based on the real-time target heat load. The theoretical flow rates of all branch pipelines are summed, and combined with the upper limit of the total circulating water volume set by the primary network, the theoretical flow rates of each branch pipeline are normalized by the global balance distribution coefficient and the user priority coefficient.

5. The method for adjusting the primary network heating flow balance and reducing the resistance of the primary pipeline system according to claim 4, characterized in that, The calculation method for the real-time target heat load is as follows: The theoretical basic heat load GH is calculated by multiplying the heating area, the design heat index per unit area, and the comprehensive building characteristic correction factor. The real-time target heat load is calculated by multiplying the theoretical basis heat load GH, the meteorological correction factor, and the operational feedback correction factor.

6. The method for adjusting the primary network heating flow balance and reducing the resistance of the primary network as described in claim 1, characterized in that, Before performing the pipeline resistance reduction operation, a diagnostic step is also included: The inspection confirmed that the dirt separators and heat exchangers in the heating stations at the end of the branch pipelines were not faulty or had excessive resistance. After confirming that the pipe diameter meets the flow requirements, the cause of the fault was determined to be internal blockage in the pipe.

7. The method for adjusting the primary network heating flow balance and reducing the resistance of the primary pipeline system according to claim 2, characterized in that, The static physical parameters on which the flow demand assessment model is based include at least: heating area, building use classification, building energy efficiency standards, pipeline terminal index, and user priority coefficient.

8. The method for adjusting the primary network heating flow balance and reducing the resistance of the primary pipeline system according to claim 2, characterized in that, The dynamic operating parameters on which the flow demand assessment model is based include at least: real-time outdoor temperature, real-time wind speed, and historical heat consumption data.

9. The method for adjusting the primary network heating flow balance and reducing the resistance of the primary network as described in claim 2, characterized in that, The specific implementation of the flow balance adjustment is as follows: In the coarse adjustment stage, based on the final target flow rate, it is determined whether the deviation between the actual flow rate of each branch pipeline and the final target flow rate is greater than a preset coarse adjustment error threshold. If so, the opening of the regulating valve is adjusted to a larger range so that the actual flow rate quickly enters a more tolerant range near the final target flow rate; In the fine-tuning stage, based on the coarse-tuning, when the deviation is less than or equal to the coarse-tuning error threshold, the regulating valve is fine-tuned in a small-amplitude, iterative closed-loop manner by continuously comparing the current deviation between the actual flow rate and the final target flow rate, with the goal of a smaller allowable range of fine-tuning error, until the deviation is stably maintained within the allowable range of fine-tuning error.

10. The method for adjusting the primary network heating flow balance and reducing the resistance of the primary network as described in claim 1, characterized in that, The operation of intermittently opening and closing the sewage outlet valve specifically involves rapidly opening and closing the sewage outlet valve at a cycle frequency of 0.5 to 4 times per minute; wherein the single opening stroke time or single closing stroke time of each valve is less than 2 seconds.

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